Link for hinge lasts



Aug. 29, 1944. G. F. RYAN 2,356,888

LINK FOR HINGE LASTS Filed Oct. 15, 1943 II I 2 M Patented Aug. 29, 1944 UNITED STATES PATENT OFFICE- assasss LINK FOR HINGE LASTS George F. Ryan, Peabody, Mass, assignor to United Shoe Machinery Corporation, Flemington, N. J., a corporation of New Jersey Application October 15, 1943, Serial No. 506,401

13 Claims.

This invention relates to hinge lasts.

In lasts of this type the heel part and the forepart are hinged together for'relative rocking movement of the parts to collapse or expand the last. The parts of such lasts have interfitting curved surfaces which constitute the last hinge and usually the parts are provided with anchor pins and the pins are connected by a link which functions to hold or assist in holding the parts in hinged relation. The anchor pins are so arranged that a line passing through their centers will be ofiset from the hinge center when the last is either expanded or collapsed. Thus, movement of the last parts from one position to another causes the anchor pins to move slightly away from one another until a dead. center position is reached and thereafter to move slightly toward one another until the movement of the last parts has been completed. To permit the anchor pins to. move in this manner the link is made resiliently extensible so that it can stretch and contract slightly as required and will function impositively to lock the last parts in either expanded or collapsed position.

When a last, such as that just described, is in expanded position within a shoe and when the bottom of the shoe is being treated with pressure while the last is being supported at its heel and toe ends, as in a leveling or a cement sole attaching machine, the pressure tends to rock the last parts so as to stretch the hinge link, and the pressure may be heavy enough to overstretch the link and thus to distort the last and damage the shoe.

One object of the present invention is to provide improved means for preventing overstretching of resiliently extensible links for hinge lasts.

With this object in view, my invention consists in the features of construction hereinafter described and claimed, the advantages of which will be apparent to those skilled in the art.

The invention will now be explained with reference to the accompanying drawing, in which Fig. 1 is a view of one side of my improved link or coupling for a hinge last;

Fig. 2 is a sectional view taken along the line 'IIII of Fig. 1;

Fig. 3 is a view of the opposite side of the link;

Fig. 4 is a view, partially in central longitudinal section and partially in elevation, of a hinge last provided with the link shown in the preceding figures, the last being shown in extended or expanded condition and in an inverted position;

Fig. 5 is a view in central longitudinal section of a portion of the last, showing it in contracted or collapsed condition; and.

Fig. 6 is a view similar to Fig. 5 but showing the heel part and the forepart of the last in the relative positions they occupy when the centers of the anchor pins are alined with the hinge center of the last during relative movement of the last parts from one position to. another.

Referring to Figs. 4 to 6, inclusive, of the drawing, the last shown therein comprises a heel part [0 and a forepart l2, the heel part being formed with a knuckle It which fits within a socket I6 in the forepart l2 toprovide for relative rocking movements of the last parts for the purpose of contracting or expanding the last. A shoulder l8 on the heel part I0, at one side of the hinge formed by the knuckle joint, is adapted to engage a cooperating shoulder120 on the forepart [2 to limit the expanding or opening movement of the last parts. At the opposite side of the knuckle joint, surfaces 22 and24 on: the ,heel part II] and the forepart l2,respectively, are arranged to cooperate to limit the collapsing or closing movement of the last parts. The two last parts are held together, with the knuckle l4 interfitting within the socket It, by means of a link or coupling 26 through the opposite end '32 and 34 in the last parts.

The interfitting surfaces of the knuckle l4 and the recess I6 are curved about a center a: which constitutes the hinge center-of the last. When the last is expanded, as shown in Fig. 4, the line :1; extending through the centers of the anchor pins 28 and 30 passes to one side of the hinge center as and when the last is collapsed or contracted, as illustrated in Fig. 5, the line y'passes to the other side of the hinge center. During movement of the last parts in. either expanding or collapsing the last the anchor pins move slightly away from one another until the dead center position illustrated in Fig. 6 is reached, after which the pins move a corresponding .dis-

I tance toward one another until the movement movement of separation of the' pinsto'" insure against damage to the last or distortion of a-shoe thereon my improved link structure is constructed as will now be explained.

As shown in Figs. 1 to 6, inclusive, the hinge link 26 is a one-piece metal stamping provided with apertures 38 for receiving the anchor pins 28 and 38. Narrow flanges 48 are struck up around the edges of the apertures 38 to provide bearing surfaces of substantial area for engagement with the anchor pins. Flange 42 extend at right angles to the body of the link structure along the opposite lateral edges thereof to strengthen the structure, the width of the flanges 42 corresponding to that of the slots 32 and 34 in the last parts so that the link will fit withoutsidewise play within th slots and thereby insure accurate alinement of the lateral edges of the opposed end faces of the last parts. The link 26 comprises a mid portion 44 which is continuous throughout the full width of the link structure and opposite end portions each of which is divided by a U-shaped slit 46 into inner link parts 48 (which contain the apertures 38 and are integral extensions of the mid portion 44.) and outer U-shaped frames 58 which are also integral. with the mid portion 44 and which peripherally surround the link parts 48. To insure against possible fracturing or deterioration of the metal adjacent to the inner ends of the slits 46 as a result of the stretching of the link parts 48, small openings 49 are formed where the slits. 46 terminate. In each link part 48 a transverse corrugation or rib 52 is formed between the aperture 38 and the mid portion 44 of the link structure, these corrugations making the link parts 48 resiliently extensible to allow for the movements of separation and approach of the anchor pins of the last as the last is being collapsed or expanded. The rest of the link structure (including the frames 58) is inextensible and substantially rigid and the inner edges 52 of the curved outer ends of the frames 50 are spaced from the adjacent edges of the link parts 48 to permit extension of these parts for the purpose above indicated. The spacing of the ends of the frames 58 from the link parts 48, however, is such that the edges 52 will function as stops engageable with the outerends of the link parts 48 so as to prevent overextension of the link parts such as might occur during the leveling of the shoe or the cement attaching of the outsole to the shoe when the last, in expanded condition, is supported at its heel and toe ends. At such times the heavy pressure of the leveling roll or the sole attachingpress may tend to rock the last parts about their meeting tread face edges so as to break the back of the last and damage the shoe. Before such rocking movement can progress sufficiently to cause injury to the shoe, however, the expanding link parts 48 will engage the edges 52 ofthe frames 58 which will then act as stops to prevent further extension of the link parts and further rocking of the last parts.

My improved link or couplin is inexpensive to manufacture inasmuch as it consists of a onepiece metal stamping and may be struck out from sheet stock and sufficiently hardened and tempered sothat it will have the desired strength and resiliency.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United Statesis: v

1. A link for a hinge last, said link comprising an inextensible mid portion, resiliently extensible end portions, and stop members connected with said mid portion and arranged to engage said end portions to permit only alimited amount of extension thereof.

2. A last part couplingfor ahinge last; said coupling comprising a resiliently extensible link portion within an inextensibl frame portion, said portions being integrally connected and relatively arranged to prevent overextension of said link portion.

3. A link unit for a hinge last, said unit comprising resiliently extensible link portions at opposite ends of a, substantially rigid mid portion, and an inextensible frame portion integral with said mid portion and peripherally surrounding said link portions, the opposite ends of said frame portion being disposed relatively to the respective outer end of said link portions to limit the extensibility of said link portions.

4. A link for a hinge last, said link comprising a mid portion integrally extending in both directions to provide at each end of the link an inner link part and an outer frame member separate from said link part, each of said link parts having an anchor pin receiving aperture and having formed therein a transverse corrugation making said part resiliently extensible and each of said frame members being disposed relatively to the respective link part to limit the extensibility of said part,

5. A coupling for a hinge last, said coupling comprising a link member having an inextensible portion and a resiliently extensible portion, and a stop member integral with said inextensible portion and engageable by said extensible portion to limit the extensibility thereof.

6. A last part coupling for a hinge last, said coupling having a stretchable link portion provided with anchor pin receiving apertures, and a non-stretchable portion surrounding said link portion in the plane of the latter and having stop shoulders arranged with respect to the end edges of said link to limit the stretchability of the link.

7. A coupling for the parts of a hinge last. said coupling consisting of a one-piece metal stamping comprising an inner link member, an outer frame, said link member having an inextensible mid portion and resiliently extensible end portions each provided with an anchor pin receiving aperture defined by an upstanding flange on said member, and said frame being inextensible and integral with the mid portion of said link member and having flanged lateral edges and its opposite end portions. being disposed relatively to the opposite ends of said link member to limit the extent to which said member can be lengthened.

8. A link for a hinge last, said link consisting of a one-piece metal stamping having in each end portion a U-shapedslit the ends of whichare located in the mid portion of the link, that part of each end portion which'is located inwardly of said slit having an anchor pin receiving aperture and being resiliently extensible, the rest of said link being inextensible,and the endportions of the link at the outer sidesof said slits being arranged relatively to said extensibleportions to limit the extensibility of the latter.

9. In a last having a heel-part and a forepart hinged together for relative rocking movements to expand and collapse the last and havingin their opposed end faces alined recesses extending lengthwise of the last' parts, a resiliently extensible coupling link housed within said recesses and having apertures-in its end portions, pins extending through said apertures and anchored in said last parts, and rigidly connected means located within said recess and engageable with the opposite ends of said link for preventing over-extension of the link.

10. In a hinge last, a forepart and a heel part adapted for relative rocking movement in one direction about a hinge center to expand the last and in the opposite direction to collapse the last, an anchor pin in said forepart, an anchor pin in said heel part, said pins being so arranged that a line passing through their centers will be ofiset from said hinge center when the last is either expanded or collapsed, a link mounted on said pins, said link being adapted to stretch and contract during each of said rocking movements, and means engageable with the ends of said link for limiting the extent to which the link is permitted to stretch.

11. In a hinge last, a forepart and a heel part adapted for relative rocking movement in one direction about a hinge center to expand the last and in the opposite direction to collapse the last, an anchor pin in said forepart, an anchor pin in said heel part, said pins being so arranged that a line passing through their centers will be off-' set from said hinge center when the last is either expanded or collapsed, a resiliently extensible link mounted on said pins, said links being capable of stretching and contracting to accommodate said rocking movements, and means engageable with the ends of said link for positively preventing the link from being stretched more than enough to permit said rocking movements to take place.

12, In a hinge last, a forepart and a heel part adapted for relative rocking movement in one direction about a hinge center to expand the last and in the opposite direction to collapse the last, an anchor pin in said forepart, an anchor pin in said heel part, said pins being so arranged that a line passing through their centers will be offset from said hinge center when the last is either expanded or collapsed, a resilient link mounted on said pins, said link being adapted to stretch and contract during each of said rocking movements, and means integral with said link and engageable with the opposite end portions thereof for limiting the extent to which said link is permitted to stretch.

13. In a hinge last, a forepart and a heel part adapted for relative rocking movements about a hinge center to expand and collapse the last, an anchor pin in said forepart, an anchor pin in said heel part, said pins being so arranged that a line passing through their centers will be ofiset from said hinge center when the last is either expanded or collapsed, a link mounted on said pins, said link being made of resilient material and being corrugated transversely to adapt it to lengthen and shorten during the rocking movements of the last parts from one position to another, and means constructed and arranged to engage the opposite ends of said link to limit the extent to which the link is permitted to lengthen.

GEORGE F. RYAN. 

